Particle-impeding and ventilated solenoid actuator

摘要

The present invention is directed to an improved solenoid 10' for providing linear actuation. The outer polepiece 16' of the solenoid is provided with a plurality of radially-dispersed labyrinthine passageways 44 in communication between the exterior of the solenoid and an interior region including the armature 20 and the interior of the windings. The polepiece is further provided with at least one passageway 52 in communication between the exterior of the solenoid and an outer periphery of the windings within the housing. The two sets of passageways impede particles and droplets of moisture from entering the solenoid, while simultaneously permitting moisture such as condensation within the solenoid to evaporate and escape.